Zimbabwe's three-day thrashing at the hands of West Indies has once again highlighted the widening disparity between the top and bottom halves of the international cricket test rankings.

The Africans only made it to halfway through the third day of five scheduled in the first of two tests on Thursday.

At first glance, the one-sided contest at the Kensington Oval here suggested the Zimbabweans are out of their depth at this level and therefore undeserving of test status.

However, a broader examination of the structure of test cricket reveals a format that limits the opportunities for struggling nations to improve standards and seriously challenge the higher-ranked countries.

Since ending a self-imposed six-year exile from test cricket in August 2011 -- caused by the domestic political situation that resulted in a mass exodus of the country's top players -- Zimbabwe had played only five test matches and none in the preceding 14 months to this one.

Despite marking their return with a victory over Bangladesh, they lost the next four, one each to Bangladesh and Pakistan and two to New Zealand, the final encounter by the massive margin of an innings and 301 runs in Napier in January 2012.

While Zimbabwe were much more competitive prior to exile, they had nonetheless never reached the upper echelons of test cricket, even when at their very strongest.

So to expect them to hold their own immediately after their return, even among the weaker opponents, would seem unrealistic.

Fundamental to the challenges faced by nations like Zimbabwe is the International Cricket Council's Future Tours Programme.

Rather than offering a fixed schedule of test, one-day international and t20 series involving all ten full-member nations on a regular basis, it is in practice a flexible guideline, adjusted and amended bi-laterally to facilitate the priorities of the higher-ranked and financially more powerful members.

Ironically, it is the same inequitable structure that has given the West Indies the opportunity to enjoy a winning streak that harkens back to their halcyon era of the 1980s, if only statistically.

The team led by Darren Sammy has now won five test matches in a row with every prospect of extending that run to six with the second and final test against Zimbabwe starting in Dominica next Wednesday.

Such continuous success has not been enjoyed by the Caribbean side since the all-conquering squad led by Vivian Richards won seven test matches in a row in 1988.

Yet the differences between the two achievements could not be more pronounced.

Back then the West Indies won the last four matches in England and the first three in Australia against experienced, battle-hardened opponents who possessed a number of quality players in their line-ups.

In contrast, the current team, which is still ranked only seventh of the ten test nations, have beaten eight-ranked New Zealand twice at home, ninth-ranked Bangladesh twice away and now the unranked Zimbabwe.

Add to that the fact that the West Indies, since defeating England by an innings in Kingston in February, 2009, have played 37 tests with only one victory over a team ranked higher than themselves (Pakistan in Guyana in May, 2011), and it becomes clear that while the team is clearly improving, they are undoubtedly flattered by their present run of success.